Platen mechanism in which angular position of each of a plurality of platen members disposed coaxially may be adjusted independently of others

ABSTRACT

A platen mechanism in which the angular position of each of a plurality of platen members coaxially disposed may be adjusted independently of the other platen members, said platen mechanism comprising a plurality of platen members disposed coaxially, each of said plurality of platen members being engaged with and disengaged from the adjacent platen member or members through a clutch or clutches, a plunger extending through said plurality of platen members and their associated clutches coaxially thereof for slidable movement in the axial direction, and means for causing said clutches to engage or disengage depending upon the shift of said plunger.

United States Patent Matsuhisa [4 1 Nov. 12, 1974 [75] Inventor: Koh Matsuhisa,Ninomiyamachi,

Japan [73] Assignee: Ricoh Co., Ltd., Tokyo, Japan [22] Filed: Nov. 15, 1972 [21] Appl, No.: 306,877

[30] Foreign Application Priority Data 1,531,875 3/1925 Ray 197/129 1,880,220 10/1932 Sundstrand 197/129 1,931,382 10/1933 Hart 197/129 2,120,360 6/1938 Hillis 197/123 2,213,552 9/1940 Scharr 197/129 2,805,748 9/1957 Christian et al. 197/129 X 3,208,575 9/1965 Emig 197/123 X Primary Examiner-Ernest T. Wright, .1 r. Attorney, Agent, or FirmCooper, Dunham, Clark, Griffin & Moran ABSTRACT A platen mechanism in which the angular position of each of a plurality of platen members coaxially disposed may be adjusted independently of the other platen members, said platen mechanism comprising a plurality of platen members disposed coaxially, each of said plurality of platen members being engaged with and disengaged from the adjacent platen member or members through a clutch or clutches, a plunger extending through said plurality of platen members and their associated clutches coaxially thereof for slidable movement in the axial direction, and means for causing said clutches to engage or disengage depending upon the shift of said plunger.

4 Claims, 1 Drawing Figure PLATEN MECHANISM IN WHICH ANGULAR POSITION OF EACH OF A PLURALHTY OF PLATEN MEMBERS DISPOSED COAXllALLY MAY BE ADJUSTED INDEPENDENTLY OF OTHERS BACKGROUND OF THE INVENTION The present invention relates to a platen mechanism for a typewriter of the type in which the angular position of each of a plurality of platen members disposed coaxially may be selectively adjusted independently of the other platen members.

It is often desired to type different data simultaneously upon a plurality of paper sheets held upon a platen. For example in an accounting machine it is desired to type the data sequentially upon ledgers and bills held on the same platen. For this purpose a platen of a typewriter preferably comprises a plurality of divided platen members which are coaxially disposed and are individually rotatable independently of the other platen members. For this purpose there has been proposed a platen of the type comprising two platen members which may be engaged with or disengaged from each other by a pin extending through holes formed through the two platen members and off the axis thereof. When the two platen members are disengaged from each other, the angular position of each of them may be arbitarily selected. However, this platen mechanism has a disadvantage that the two platen members may be engaged with each other only when the holes of the two platen members are aligned with each other. Therefore the platen mechanism of the type described cannot be applied to a platen comprising a plurality of platen members.

SUMMARY OF THE INVENTION One of the objects of the present invention is therefore to provide a multi-platen mechanism of the type in which a plurality of divided platen members may be rotated in unison and are disengaged from each other so that the angular position of each of the plurality of platen members may be selectively adjusted independently of the other platen members.

According to one embodiment of the present invention, a plurality of divided platen members are engaged with and disengaged from each other through clutches. A ratchet wheel which is driven by a suitable driving mechanism is engaged with and disengaged from the platen mechanism through a spring loaded clutch. The plurality of platen members are fitted over a hollow shaft into which is in turn fitted a plunger. A collar which is slidably fitted over the hollow shaft has a pin which is fitted into an axially elongated slot formed in the hollow shaft and is fixed to the plunger. Each end of the collar is coupled to a respective clutch through a thrust bearing so that when the plunger is shifted to the right or left the collar is caused to move to the right or left, thereby engaging or disengaging the respective clutch. Therefore the platen members may be selectively engaged with or disengaged from each other.

The above and other objects, features and advantages of the present invention will become more apparent from the following description of one preferred embodiment thereof taken in conjunction with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING The single FIGURE is a side view, partly in section, of a multi-platen mechanism in accordance with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the single FIGURE a platen in accordance with the present invention is shown as comprising three platen members 100, 200 and 300. Spring loaded clutches 10 and 15 are disposed within the platen member at both ends. The clutch 10 comprises a stationary cylindrical member 1 1 securely fixed to the first platen member 100 with a screw 14 and an axially movable disk-shaped member 12 disposed within the stationary member 11. The tapered side 12' of the movable member 12 is normally pressed against the mating tapered portion 11' under the force of a spring 13. The clutch 15 is similar in construction to the clutch 10 except that an axially movable diskshaped member 17 is provided with a stud 20. That is,

the clutch 15 comprises a stationary cylindrical member 16 fixed to the platen member 100 with a screw 19 and the movable member 17 whose tapered portion 17' is normally pressed against the mating tapered portion 16' of the stationary member 16 under the force of a spring 18.

Two thrust bearings 22 and 27 are disposed within the platen member 200 at both ends thereof. The thrust bearing 22 is positioned within a sleeve 23 fitted into and securely fixed to the second platen member 200 with a screw 24. At the bottom of the sleeve 23 is formed a through hole 23 into which is fitted the stud 20 extending from the movable member 17 in opposed relation with one surface of the thrust bearing 22. A retaining ring 25 is fitted into the sleeve 23 in order to limit the movement of the thrust bearing 22. The thrust bearing 27 is disposed in a manner substantially similar to that of the thrust bearing 22. That is, the thrust bearing 27 is located in a sleeve 28 fitted into and securely fixed to the second platen member 200 with a screw 29,

and a retaining ring 30 is fitted into the sleeve 28 so that the movement of the thrust bearing 27 may be limited within the sleeve 28.

At one end of the third platen member 300 in opposed relation with the second platen member 200 is disposed a clutch 31 which is substantially similar in construction to the clutches 10 and 15 disposed in the first platen member 100. A stud 36 extending from an axially movable disk-shaped member 33 of the clutch 31 is extended through a through hole 28' formed in the bottom of the sleeve 28 of the thrust bearing 27 in opposed relation therewith. The movable member 33 is normally pressed against a stationary member 32 fixed to the third platen 300 with a screw 35 under the force of a spring 34.

Through the center holes of the clutches 10, 15 and 31 and the thrust bearings 22 and 27 is inserted a hollow shaft 37 into which is in turn fitted a plunger 38 for slidable movement in the axial direction. A pin 39 which is fixed to a collar 40 fitted over the hollow shaft 37 and which extends through the left end of the plunger 38 is fitted into an axially elongated slot 37' formed in the hollow shaft 37. The collar 40 is interposed between the pair of thrust bearings 22 and 27 in the second platen member 200.

A sleeve 41 having a flange 41 is fitted over the right end portion of the hollow shaft 37 and into the center hole of the clutch 10. The flange 41' is securely fixed to the stationary member 11 of the clutch It) with a screw 42. The sleeve 41 carries a ratchet wheel 43 whichin turn is drivingly coupled to a suitable driving member not shown. A stud 44 extending inwardly from the ratchet wheel 43 is fitted into a through hole 44' formed in the movable member 12 of the clutch 110. The ratchet wheel 43 is engaged with and disengaged from the platen through an operating lever 45. At the right end of the plunger 33 are formed three annular grooves 38, 38" and 38, and a ball 46, which is fitted into a hole 46' of the hollow shaft 37 and is biased to move radially under the force of a rubber tube 47 fitted over the hollow shaft 37, is fitted into one of the three annular grooves 38', 38" or 38". A sleeve 50 is interposed between the ratchet wheel 43 and a knob 48 fitted over and fixed to the hollow shaft 37 with a screw 49. A knob 51 is fixed to the right end of the plunger 38.

It is assumed that the ball 46 is fitted into the central annular groove 38" as shown in the FIGURE. Then the tapered portion 16' of the stationary member 16 of the clutch 15 in the first platen member 100 is in engagement with the tapered portion 117' of the movable member 17. Similarly the movable member 33 of the clutch 31 in the third platen member 300 is in engagement with the stationary member 32. The stud 20 of the movable member 17 is fitted into the hole 23 of the sleeve 23 fitted over the thrust bearing 22in the second platen member200 whereas the stud 36 of the movable member 33 of the clutch 31 in the third platen member 300 is fitted into the hole 28' of the sleeve 28 fitted over the thrust bearing 27 in the second platen member 200. That is, the platen members 100, 200 and 300 are engaged with one another. When the operating lever 45 is shifted in the direction indicated by the arrow, the movable member 12 is disengaged from the stationary member of the clutch so that the ratchet wheel 43 is disengaged from the platen mechanism. When the knob 48 is rotated, the platen members 100, 200 and 300 are rotated in unison so that their angular positions may be arbitarily selected.

When the knob 51 is pulled to the right, the plunger 38 is shifted to the right so that the ball 46 now engages with the first annular groove 38' and the collar 40 slides over the hollow shaft 37 to the right to push the thrust bearing 22 so that the movable member 17 of the clutch is caused to move toward the right against the spring 18 and is disengaged from the stationary member 16. As a result, the first platen member 100 is disengaged from the second platen member 200 whereas the second platen member 200 remains in engagement with the third platen member 300. Therefore the angular position of the first platen member 100 may be now freely selected independently of the second and third platen members 200 and 300.

When the knob 51 is pushed to the left from the position shown in the FIGURE, the plunger 38 is moved toward the left and the ball 46 engages with the annular groove 38". The collar 40 is caused to slide over the hollow shaft 37 to push the thrust bearing 27 which in turn pushes to the left the movable member 33 of the clutch 31 in the third platen member 3% so that the former is disengaged from the latter. As a result the third platen member 300 is disengaged from the first and second platen members and 200 so that its angular position may be freely adjusted independently of the latter.

After the angular positions of the platen members R00, 204) and 300 have been adjusted in the manners described above, the plunger 38 is returned to its normal position by the knob 51, that is the position in which the ball 46 is engaged with the central annular groove 38" as shown in the FIGURE so that the platen members 11%, 200 and 30th are engaged with one another. Therefore when the lever 45 is operated so as to cause the movable member 12 to engage with the stationary member 111 of the clutch 10 in the first platen member 1%, the rotation of the ratchet wheel 43 is now transmitted to the first, second and third platen members 100, 200 and 300 through the clutches 10, 15 and 31.

The present invention has been described so far with reference to only one example thereof and it will be understood that various modifications and variations may be effected without departing the scope of the present invention. For example the platen mechanism may be arranged and constructed on the left side in a manner substantially similar to that described hereinbefore.

What is claimed is:

I. A platen mechanism in which the angular position of each of a plurality of platen members coaxially disposed may be adjusted independently of the other of said platen members, said platen mechanism comprismg a. a plurality of platen members disposed coaxially,

b. clutches for individually engaging and disengaging each of said plurality of platen members with each other platen member adjacent thereto, each of said clutches comprising i. a stationary member disposed at one end of one of said plurality of platen members and ii. a movable member disposed at one end of the platen member adjacent to said one platen member in opposed relation with said one end of said one platen member for slidable movement, said movable member being normally spring-biased into engagement with said stationary member but movable away from said stationary member against said spring bias thereby disengaging said clutch,

c. a hollow shaft extending through said plurality of platen members and said clutches coaxially thereof,

d. a plunger slidably fitted into said hollow shaft,

and

e. slidable means, connecting to said plunger and slidable over said hollow shaft in response to the shift of said plunger, for causing said clutches to engage or disengage, said slidable means including a pin for connecting said slidable means to said plunger, and said hollow shaft having an axially elongated slot through which said pin extends.

2. A platen mechanism as defined in claim I further including a plurality of thrust bearings fitted over said hollow shaft for respectively operatively coupling said slidable means to the movable members of said clutches.

shaft and biased to selectively engage with one of 5 said plurality of annular grooves.

4. Platen mechanism comprising a. a plurality of coaxial, independently rotatable platen members including first and second platen members and a third platen member interposed between said first and second platen members;

b. clutch means for disengageably interconnecting each of said platen members with each adjacent other one of said platen members for rotation therewith, each of said clutch means comprising i. an annular clutch seat mounted fixedly and coaxially within one of two adjacent platen members,

platen members with the clutch members of said pair of clutch means respectively interconnected with opposite ends of said third platen member;

c. a plunger extending through said platen members and clutch means along the common axis thereof and longitudinally movable relative thereto;

d. a hollow shaft extending cozaxially through said first, second and third platen members and said pair of clutch means in surrounding relation to said plunger, said shaft having an axially elongated slot within said third platen member; and

e. clutch-member-displacing means operatively connected to said plunger, and movable therewith along said common axis, for engaging and displacing the clutch member of each said clutch means out of engagement with the clutch seat of the respective clutch means upon movement of said plunger in a given direction along said common axis, said clutch-member-displacing means comprising a sleeve concentrically surrounding said shaft within said third platen member and axially slidable relative to said shaft between an inoperative central position and opposed first and second positions for respectively displacing the clutch members of the clutch means respectively mounted in said first and second platen members out of engagement with the respective clutch seats of said clutch means, and means connecting said sleeve and plunger through said slot.

=l= =i= =i Il= 

1. A platen mechanism in which the angular position of each of a plurality of platen members coaxially disposed may be adjusted independently of the other of said platen members, said platen mechanism comprising a. a plurality of platen members disposed coaxially, b. clutches for individually engaging and disengaging each of said plurality of platen members with each other platen member adjacent thereto, each of said clutches comprising i. a stationary member disposed at one end of one of said plurality of platen members and ii. a movable member disposed at one end of the platen member adjacent to said one platen member in opposed relation with said one end of said one platen member for slidable movement, said movable member being normally spring-biased into engagement with said stationary member but movable away from said stationary member against said spring bias thereby disengaging said clutch, c. a hollow shaft extending through said plurality of platen members and said clutches coaxially thereof, d. a plunger slidably fitted into said hollow shaft, and e. slidable means, connecting to said plunger and slidable over said hollow shaft in response to the shift of said plunger, for causing said clutches to engage or disengage, said slidable means including a pin for connecting said slidable means to said plunger, and said hollow shaft having an axially elongated slot through which said pin extends.
 2. A platen mechanism as defined in claim 1 further including a plurality of thrust bearings fitted over said hollow shaft for respectively operatively coupling said slidable means to the movable members of said clutches.
 3. A platen mechanism as defined in claim 1 further comprising a plurality of annular grooves formed around said plunger, and a ball fitted into a lateral hole formed in said hollow shaft and biased to selectively engage with one of said plurality of annular grooves.
 4. Platen mechanism comprising a. a plurality of coaxial, independently rotatable platen members including first and second platen members and a third platen member interposed between said first and second platen members; b. clutch means for disengageably interconnecting each of said platen members with each adjacent other one of said platen members for rotation therewith, each of said clutch means comprising i. an annular clutch seat mounted fixedly and coaxially within one of two adjacent platen members, ii. a clutch member interconnected with the other of the two adjacent platen members for coaxial rotation therewith, and movable along the common axis thereof into and out of rotation-transmitting engagement with said seat in maintained interconnection with said other platen member, the clutch member and clutch seat being shaped for rotation-transmitting interengagement at any relative angular orientations thereof about said common axis, and iii. means resiliently biasing said clutch member into engagement with said clutch seat, said clutch means including a pair of said clutch means respectively mounted in said first and second platen members with the clutch members of said pair of clutch means respectively interconnected with opposite ends of said third platen member; c. a plunger extending through said platen members and clutch means along the common axis thereof and longitudinally movable relative thereto; d. a hollow shaft extending coaxially through said first, second and third platen members and said pair of clutch means in surrounding relation to said plunger, said shaft having an axially elongated slot within said third platen member; and e. clutch-member-displacing means operatively connected to said plunger, and movable therewith along said common axis, for engaging and displacing the clutch member of each said clutch means out of engagement with the clutch seat of the respective clutch means upon movement of said plunger in a given direction along said common axis, said clutch-member-displacing means comprising a sleeve concentrically surrounding said shaft within said third platen member and axially slidable relative to said shaft between an inoperative central position and opposed first and second positions for respectively displacing the clutch members of the clutch means respectively mounted in said first and second platen members out of engagement with the respective clutch seats of said clutch means, and means connecting said sleeve and plunger through said slot. 